Research On Driving System Control Strategy Of A Permanent Magnet Synchronous Linear Motor In High Precision Conditions

There are many higher requirements such as accuracy, fast-response, stability for servo system, as industrial control used in high precision situation. The traditional mechanical processing becomes more difficult to meet this need. The electrical energy can be transferred into mechanical energy of linear motion by permanent magnetic synchronous linear motors(PMSLMs) which has the characteristics of simple structure, high efficiency, high precision, and all intermediate mechanism can be canceled. So it is widely used in high-grade precision occasions.This thesis selected pairs of secondary permanent magnet synchronous linear motor as the research platform. Focus on the exists thrust ripple, difficult to detect the initial position accurately, too many external disturbances, the author started with all of this, then researched step by step, special steps as follows:(1)The author tried to analyze and deduct for voltage, flux, electromagnetic torque and mechanical equations of motion of linear motor, found out the control parameters that directly related to flux and electromagnetic torque. What is more, stress distribution in the movement process of linear motor made profound analysis, fundamentally found out the factors influencing the thrust fluctuation, and the discus was made on the whole about the source of disturbance in high precision situation.(2)Due to the linear motor direct input of the control signal is generated by the inverter, and it is the primer many classic control algorithm treat the linear motor and inverter as a whole to study, so the author made a research on the working principle of inverter, and put forward optimization efforts in the angle of the inverter linear motor control performance of the scheme. The author selected vector control as basic control, deducted detailed two forms of Clarke transform used in SVPWM, gave clear description of the source of the arguments, decoupled control for linear motor, so as to improve accuracy of controlling.(3)It is very important factor affected the accuracy of motor control linear motor of the initial position. It must not be allowed that swing back, larger dithering, and so on happened when the linear motor connecting to the power. The author estimated the initial position of linear motor based on summarizing the initial position estimation method.(4)In view of the linear motor in the process of running interference, the author introduced a method of combined PID algorithm with disturbance observer to ensure the operation stability, and we also analyzed the control strategy by the simulation analysis.(5)The author used the high performance chip TMS320F2812 of TI company as the main control chip, and strived to reduce interference sources in the hardware circuit designing, ensured the accuracy and correctness of control signals, and demonstrated the proposed control method on this hardware platform.